1. Field of the Invention
The present invention relates generally to apparatus for extruding flowing, viscous substances, and more particularly to apparatus for extruding distinct such substances in predetermined ratios in one piece without significant inter-mixture of substances.
2. Description of the Prior Art
There are numerous uses for apparatus which extrude materials. Some of these uses require that an extrudate be composed of multiple, distinct components. For example, it is often desirable to have epoxy resin and curing agent in single extrudate for the sake of convenience. In this way, the components may be cut from a length of the extrudate, and they will already be present in the desired ratio of components. Yet, when there are two components of an epoxy compound in a single extrudate, they must remain unmixed before use in order to prevent premature curing. Thus, there is a need for an apparatus which is capable of producing an extrudate composed of distinct, unmixed components. Such an apparatus should have a simple mechanism for controlling the relative ratios of the components in the extrudate, and for ensuring that the linear flow rates of the components of the extrudate are identical, thereby avoiding flow friction between the components and consequent mixing of the components with one another. Numerous extrusion apparatus have been invented, but none fully meets this clearly defined need.
U.S. Pat. No. 3,383,096, issued on May 14, 1968, to Mario Braibanti, et al., describes an apparatus for mixing alimentary pastes. The apparatus has multiple vats in which blades propel a mixture to passages disposed at bottom ends of the vats. A conveying screw receives the mixture. The apparatus is designed to ensure a particular consistency in bread dough. The patent does not suggest any way to keep distinct ingredients in a combination of ingredients separate from one another, or any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
U.S. Pat. No. 4,124,307, issued on Nov. 7, 1978, to Ladislav Anisic, describes a homogenizer for viscous substances. The homogenizer uses screws to force a mass through rotary bodies in annular grooves. The patent teaches away from keeping distinct ingredients in a combination of ingredients separate from one another, and does not suggest any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
U.S. Pat. No. 4,467,969, issued on Aug. 28, 1984, to Jack F. Godfrey, et al., describes a reclamation system that uses augers to transfer chopped resin to be mixed with virgin resin. The patent teaches away from keeping distinct ingredients in a combination of ingredients separate from one another, and does not suggest any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
U.S. Pat. No. 4,802,140, issued on Jan. 31, 1989, to Edward H. Dowling, describes an injection molding method and apparatus. The apparatus has an outer screw that rotates and plunges forward to inject plastic. There is an inner screw that remains stationary. The patent does not suggest any way to keep distinct ingredients in a combination of ingredients separate from one another, or any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
U.S. Pat. No. 4,859,068, issued on Aug. 22, 1989, to Giovanni Sironi, shows a screw type extruder with inner and outer flow chambers defined by a single, hollow screw having external and internal threads. The chambers can communicate with one another or they can be separated. When they are separated, they can extrude two layers of different materials. The patent does not suggest any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
U.S. Pat. No. 5,230,476, issued on Jul. 27, 1993, to Marcus Rust, et al., describes a vertical grinding and mixing tower having dual tanks. The tower is designed to provide for the grinding and mixing of diverse elements to produce feed. The patent teaches away from keeping distinct ingredients in a combination of ingredients separate from one another, and does not suggest any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
U.S. Pat. No. 5,253,994, issued on Oct. 19, 1993, to Konrad Zweig, et al., describes a system for molding a synthetic resin using plastic scraps. The system has a receptacle for recycled granules and a receptacle for virgin granules. The recycled granules are filtered and then mixed with virgin granules. The patent teaches away from keeping distinct ingredients in a combination of ingredients separate from one another, and does not suggest any way to maintain identical linear flow rates of distinct ingredients despite different volumetric flow rates. The patent also does not suggest variation of an output nozzle configuration for the purpose of varying ratios of ingredients in a combination of ingredients.
None of the above patents demonstrates the use of an adjustable electronic/optical sensor that determines the output of the extrusion in order to determine when it should be cut. None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.